Panoramic Radiographic Assessment of Agenesis of Mandibular Third Molars: A Hospital Based Study in Eastern Nepal

Abstract

Introduction: Racial variation, genetic inheritance and various other factors can affect the jaw size and ultimately the tooth size and number. Studies for agenesis of mandibular third molars (M3s) have been carried out in various populations but data relating to these are not evident from most of the parts of Nepal. Hence, the objective of the present study is to determine the prevalence of agenesis among the population of patients visiting the Department of Oral Medicine and Radiology of this institute. The study also sought the odds of agenesis of M3 in one side when there was missing M3 on the other side of the mandible. Methods: This study was conducted after the approval from Institutional Review Committee of BPKIHS. Two hundred and eighty four patients (568 sites of M3, bilaterally), visiting the Department of Oral Medicine and Radiology were studied with Panoramic Radiograph to assess for agenesis of mandibular third molars, bilaterally. Percentage of agenesis was calculated and chi square test was applied where relevant. Odds ratio was also calculated. Results: Agenesis was seen in 28.7% of the participants. The Odds of M3 being missing on one side with concurrent missing M3 on the other side was 40.27 (Confidence Interval 19.34 to 83.87). Conclusions: Agenesis was highly prevalent in this study group. The likelihood of M3 being absent on one side, when there was concurrent missing M3 on the other side of mandible was also high.

Keywords

• anodontia; mandible; molar; Nepal; panoramic radiography.